While on the subject of DNA, I should mention the blood disorder called hemochromatosis. Most people have never heard of this disorder, and very few physicians even understand it.
Due to my nephew developing this disorder (& almost dying from it) my family has become very aware of the disorder. From the info I have seen if you are of Celtic origin it is reported that 1 in 4 carry the gene. However I don't wish to be an alarmist. If you do have hemochromatosis, it is not a death sentence unless you do not take care of yourself.

I had the blood test & found I do not have it, however I could still be a carrier of the mutated gene and pass it along to my children. Unfortuantly, do to the high cost of a DNA test I am going round & round with my doctor to test, because of the insurance companies balking. So be forewarned, unless you show symptoms, your insurance company maynot wish for the tests to be carried out.

This from my sister who has studied the disorder, along with a link with more info:

"a person has to inherit two copies of the hemochromatosis gene to develop severe symptoms. Everyone has two HFE genes, but a person with hereditary hemochromatosis has inherited two mutated genes from each parent (mutation of chromosome 6 in the HFE gene). Basically every child of a parent that has HHC has a 50% chance of inheriting the disease only if the other parent has the mutated gene as well. So, it isn't one parents "fault" (not that there is any fault at all). Hemochromatosis is the most common genetic disorder affecting every 1 in 200 to 400 people.
If you are of Celtic origin 1 in every 4 people carry the gene for this disease.

If both parents have the gene, each of their children have a 50% chance of getting this disease - thus Anthony does not have it and Marcus does. A parent can have the mutated gene and be a "carrier" but they will not develp any symptoms as they are only a carrier of the gene. If your spouse also carries the gene then your children have a 50% chance of getting the disease.

Does this kind of make sense? A website that is fairley good with some diagrams and such on the cells, etc. (if you are interested) is: http://www.yourgenesyourhealth.org/hc/whatisit.htm "